Apparatus for elevating the interior contents of a refrigeration unit

ABSTRACT

A storage insert for a top opening storage unit, such as a freezer, comprises an outer frame shaped to fit within the top-opening unit, and an inner frame movably mounted to the outer frame for up and down movement relative to the outer frame. Horizontal shelves are mounted on the inner frame, and a lifting assembly is operatively connected between the inner and outer frames to selectively raise and lower the inner frame relative to the outer frame.

TECHNICAL FIELD AND BACKGROUND OF THE INVENTION

This invention relates to improvements in household refrigeration units, and more particularly to household refrigerators and freezers of the top-opening type.

A major fault of conventional side-opening freezer and refrigerator units (side-opening units) is that when one of these units is opened, cold air within the unit, being heavier than the warm air of the surrounding room, flows out through the lower portion of the unit's doorway and is replaced by warm air which flows into the unit through the upper portion of the doorway. This necessitates a re-cooling of most of the interior volume of the unit every time the unit's door is opened. This fault is largely remedied by top-opening freezer and refrigerator units (top-opening units). When one of these units is opened, the cold air within the unit, being heavier than the air of the surrounding room, stays inside of the unit's compartment. The only increase in temperature is caused by the momentary contact between the air within the unit and the outside air. This increase is negligible when compared to the temperature increase caused by briefly opening a side-opening unit.

The disadvantage of a top-opening unit lies in the inaccessibility of goods stored in the bottom of the unit's well or compartment. When a top-opening unit is utilized to capacity, boxes and packages are piled on top of each other. To access an article at the bottom of a full unit, overlying articles must first be removed by hand, a distinctly uncomfortable and inconvenient exercise. Accessing an article at the bottom of a top-opening unit also reduces the efficiency of the unit, as the unit must be kept open during the hand sorting of its contents.

Prior art attempts to solve the accessibility problem have included the use of baskets which hang from the top of the freezer into the interior. The baskets are removed to access the lower items. Typically the number of baskets is limited so that the baskets can be manually slid to one side or the other to access the area under the basket without actually removing the basket.

It is also known to provide vertical dividers to divide the freezer interior into a plurality of vertical compartments. Thus a much smaller number of upper items need to be removed to access items at the bottom of the compartment, since the dividers prevent adjacent items from falling into the space that is being opened to access the bottom.

A problem with removing upper items or whole baskets of items to access lower items is that occasionally the item or basket is forgotten in a location outside the freezer where it was placed while accessing lower items. Such items can spoil quickly if the error is not discovered in a short time.

SUMMARY OF THE INVENTION

It is an object of the present application to provide a top-opening refrigeration unit that overcomes problems in the prior art. The present invention provides improved accessibility in an energy efficient top-opening refrigeration unit such as is used for freezing or cooling contents.

In a first embodiment the present invention provides a storage insert for a top opening storage unit. The insert comprises an outer frame shaped to fit within the top-opening unit, and an inner frame movably mounted to the outer frame for up and down movement relative to the outer frame. At least one substantially horizontal shelf is mounted on the inner frame, and a lifting assembly is operatively connected between the inner and outer frames to selectively raise and lower the inner frame relative to the outer frame.

In a second embodiment the present invention provides a top opening refrigeration unit comprising a main body having a substantially horizontally oriented open top, and a door pivotally attached along a top edge of the main body and movable from a closed position covering the open top, to a raised open position. An inner frame is movably mounted inside the main body such that the inner frame can move relative to the main body from a lowered position inside the main body, to a raised position at least partially above the open top of the main body. At least one substantially horizontal shelf is mounted on the inner frame, and a lifting assembly is operatively connected between the inner frame and the main body to selectively raise and lower the inner frame.

In a third embodiment the present invention provides a method of providing access to an interior of a top opening storage unit. The method comprises mounting at least one substantially horizontally oriented shelf within the interior of the storage unit and operatively connecting the at least one shelf to a selectively operable lifting mechanism for vertically raising and lowering the at least one shelf relative to the unit's interior.

The present invention thus provides a simple apparatus for mechanically lifting the interior contents of a top-opening unit, thus making the contents of the unit easily accessible. The lifting apparatus can be configured to be easily installed in existing top-opening units, or integrated into a storage unit such as a freezer or the like during manufacture. It is contemplated that the lifting apparatus will allow efficient use of a significantly larger proportion of the available volume of the freezer interior compared to the prior art, and combined with drawer type shelves or rotating shelves the convenience and capacity can be increased still further.

BRIEF DESCRIPTION OF THE DRAWINGS

While the invention is claimed in the concluding portions hereof, preferred embodiments are provided in the accompanying detailed description which may be best understood in conjunction with the accompanying diagrams where like parts in each of the several diagrams are labeled with like numbers, and where:

FIG. 1 is a schematic perspective view of an embodiment of the insert of the present invention and a top-opening unit where the insert may be installed;

FIG. 2 is a schematic cut-away perspective view of the threaded rod lift assembly used in the embodiment of FIG. 1;

FIG. 3 is a schematic top view of an alternate embodiment of the insert of the present invention using a cable and pulley lift assembly and installed in a freezer;

FIG. 4 is a schematic front view of the embodiment of FIG. 3;

FIG. 5 is a schematic illustration of a lifting mechanism provided by pneumatic cylinders powered by pressurized refrigerant fluid from a refrigeration unit.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT AND BEST MODE

As shown in FIG. 1 an apparatus in the nature of a storage insert 100 according to an embodiment of the present invention comprises an inner frame 102 having walls 101 and shelves 103, and an outer frame 104 having walls 105 and a floor 106. The walls 101, 105 and floor 106 provide the required structural integrity to the inner and outer frames 102, 104. Sufficient structural integrity could also be provided by a frame work of braces or the like, as will be recognized by persons skilled in the art.

The outer frame 104 is shaped to fit within the storage unit such as the illustrated top-opening freezer unit 200 with a hinged door 202 covering the open top of a storage compartment 204 inside the freezer. Similar refrigeration units are known that only cool the contents instead of freezing same, and the storage insert 100 could be configured readily for use in these units as well. The inner frame 102 is movably mounted to the outer frame 104 for up and down movement relative to the outer frame 104. In the embodiment of FIG. 1 the inner frame 102 is essentially a box that fits in a sliding relationship inside a slightly bigger box that is the outer frame 104. Stability for inner frame 102 when elevated is also provided by the sliding proximity of inner frame walls 101 to outer frame walls 105. A plurality of horizontal shelves 103 are mounted on the inner frame 102.

When inner frame 104 of insert 100 is in its lowest position, the insert fits inside storage compartment 204 and door 202 can be opened and closed without interference. In the illustrated embodiment, the insert 100 is shaped to fit beside the freezer's compressor housing 206 in the bottom of the compartment 204.

The illustrated shelves 103 can be simple flat surfaces or drawers could be provided instead to both increase the capacity by utilizing more of the available volume of the freezer interior, and further facilitate easy access to items on the rear portion of the shelves. Horizontal shelf 103B is laterally slidable with respect to the inner frame 102, and includes side panels 119 forming a drawer that can slide in and out to provide improved access to the items at the rear of the shelf 103B, and also increase the capacity of the shelf 103B by ensuring that items placed on the shelf remain on the shelf. Similarly it is contemplated that a lazy-susan type rotating shelf might be utilized advantageously as well.

As seen in FIG. 2 a lifting assembly 110 is attached to the floor 106 of outer frame 104. The lifting assembly 110 is operatively connected between the inner and outer frames 102, 104 to selectively raise and lower the inner frame 102 relative to the outer frame 104. The lifting assembly 110 includes a motor 112, and a drive mechanism actuatable by the motor and configured such that when the motor 112 rotates in a first direction the inner frame 102 moves upward relative to the outer frame 104, and such that when the motor 112 rotates in an opposite second direction the inner frame 102 moves downward relative to the outer frame 104.

In the illustrated embodiment the motor 112 is operatively connected to a drive mechanism comprising a rotating screw actuator 114, which turns a threaded rod 116. The threaded rod 116 extends substantially vertically into a threaded aperture defined in a substantially horizontal base support member 107 that is attached to the bottom shelf 103A. Rotation of the rod 116 in one direction raises the inner frame 102 and rotation in the other direction lowers the inner frame 102.

When a user activates motor 112 using for example an externally mounted switch, motor 112 rotates screw actuator 114 which rotates threaded rod 116. The rotating rod 116 causes the threaded base support 107 to move upward. Inner frame 102, fixedly attached to lower shelf 103A and thus to threaded base support 107, moves in concert. Thus, inner frame 102 and shelves 103 and any containers or items on the shelves of the inner frame move upwardly for easy access.

To lower inner frame 102, motor 112 is activated to rotate in the opposite direction, and thus rotate the rod 116 in the opposite direction until inner frame 102 is fully lowered into the freezer.

FIGS. 3 and 4 illustrate an alternate storage insert 300 comprising a network of pulleys 316 and cables 318 connected to the inner frame 302 and the outer frame 304. A cable drum 314 is rotatably attached to a bottom portion of the outer frame 304 about a substantially vertical axis DA. The cables 318 are connected to the drum 314 and the drum 314 is connected to be rotated by the motor 312 and the drive mechanism 310 to raise and lower the inner frame 304.

In the alternate insert 300, instead of taking the form of a small box inside a larger box as in the embodiment of FIGS. 1 and 2, the outer frame 304 comprises four upright frame members 324 configured to be located in a central portion of the freezer 400, and the inner frame 302 extends out to the ends of the freezer 400 to just fit inside the freezer compartment. When moving up and down the inner frame 302 is maintained in position by its close proximity to the ends of the freezer compartment. The bottom of the inner frame 302 is configured to fit above the freezer's compressor housing 406 in the bottom of the compartment 404. While the inner frame 302 is illustrated without any shelves mounted thereon for clarity of illustration, those skilled in the art will recognize that shelving can be readily added in a variety of ways.

The storage insert 300 comprises upper and lower front right, upper and lower front left, upper and lower rear right, and upper and lower rear left pulleys 316 attached to the upper and lower ends of the upright frame members 324. A front right cable 318A is wrapped on the drum 314 and passes from the drum 314 to the lower front right pulley 316LFR, then up to the upper front right pulley 316UFR, then down to the inner frame 302. Cables 318B, 318C, and 318D are similarly wrapped on the cable drum 314 and pass through pulleys 316 on the other upright frame members 324 to the inner frame 302 such that the inner frame is supported in a horizontal position as illustrated. As the motor 312 rotates the drum 314 the cables wind onto the drum 314 to raise the inner frame 302, and when the motor 312 rotates in the opposite direction, the weight of the inner frame 302 draws the cables 318 off the drum 314 and the inner frame moves down.

The insert of the invention is adaptable to existing freezers and like storage units by properly configuring the insert to fit the unit desired. The insert can also be incorporated during manufacture. The lift assembly, pulleys, drive mechanism, and the like can be mounted directly as required on the main body of the freezer unit, instead of on an outer frame that would be inserted into the freezer compartment.

It will be appreciated by the person skilled in the art that the lifting assembly can be hydraulically or pneumatically actuated. Other lifting mechanisms could be used, for example meshing rack and pinion gears or pneumatic lift cylinders could be located at the corners of the freezer. For example FIG. 5 illustrates a lifting mechanism comprising a plurality of pneumatic cylinders 425. One cylinder 425 is located at each corner of the freezer, and the cylinders 425 are actuated by pressurized refrigerant fluid from the freezer refrigeration system. The refrigeration system includes a compressor 427 operative to draw refrigerant fluid from the low pressure side of the system LP, compress the fluid, and direct same into the high pressure side of the system HP.

Pressurized refrigerant fluid from the high pressure side HP is connected to a control valve 429, and through the valve 429 to the cylinders 425 which are slaved so as to move up and down together to raise and lower the inner frame and shelves. The return line from the last slaved cylinder 425 is connected to the control valve 429 and through same to the low pressure side of the system LP. Reservoirs 431 are added to both the high pressure side HP and low pressure side LP of the system to provide sufficient capacity to operate the system satisfactorily using a conventional freezer compressor. The pressurized refrigerant system of the freezer or like refrigeration unit could also similarly be connected to power a motor in a lifting mechanism.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous changes and modifications will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all such suitable changes or modifications in structure or operation which may be resorted to are intended to fall within the scope of the claimed invention. 

1. A storage insert for a top opening storage unit, the insert comprising: (a) an outer frame shaped to fit within the top-opening unit; (b) an inner frame movably mounted to the outer frame for up and down movement relative to the outer frame; (c) at least one substantially horizontal shelf mounted on the inner frame; and (d) a lifting assembly operatively connected between the inner and outer frames to selectively raise and lower the inner frame relative to the outer frame.
 2. The storage insert of claim 1 wherein the lifting assembly includes a motor, and a drive mechanism actuatable by the motor and configured such that when the motor rotates in a first direction the inner frame moves upward relative to the outer frame, and such that when the motor rotates in an opposite second direction the inner frame moves downward relative to the outer frame.
 3. The storage insert of claim 2 comprising a threaded rod engaged in a threaded aperture in the inner frame and connected to be rotated by the drive mechanism.
 4. The storage insert of claim 3 wherein the threaded rod extends substantially vertically into the threaded aperture defined in a substantially horizontal base support member.
 5. The storage insert of claim 2 comprising a plurality of pulleys and at least one cable connected to the inner frame, the outer frame, and the drive mechanism and configured to raise and lower the inner frame.
 6. The storage insert of claim 5 comprising a cable drum rotatably attached to a bottom portion of the outer frame about a substantially vertical axis and connected to the at least one cable and connected to be rotated by the motor and the drive mechanism.
 7. The storage insert of claim 6 comprising: (a) upper and lower front right, upper and lower front left, upper and lower rear right, and upper and lower rear left pulleys attached to the outer frame; (b) a front right cable wrapped on the drum and passing from the drum to the lower front right pulley, then up to the upper front right pulley, then down to the inner frame; (c) a front left cable wrapped on the drum and passing from the drum to the lower front left pulley, then up to the upper front left pulley, then down to the inner frame; (d) a rear right cable wrapped on the drum and passing from the drum to the lower rear right pulley, then up to the upper rear right pulley, then down to the inner frame; and (e) a rear left cable wrapped on the drum and passing from the drum to the lower rear left pulley, then up to the upper rear left pulley, then down to the inner frame.
 8. The storage insert of claim 1 wherein the lifting assembly comprises a plurality of pneumatic cylinders.
 9. The storage insert of claim 1 wherein the at least one substantially horizontal shelf is laterally slidable with respect to the inner frame, and includes side panels forming a drawer.
 10. A top opening refrigeration unit comprising: (a) a main body having a substantially horizontally oriented open top, and a door pivotally attached along a top edge of the main body and movable from a closed position covering the open top, to a raised open position; (b) an inner frame movably mounted inside the main body such that the inner frame can move relative to the main body from a lowered position inside the main body, to a raised position at least partially above the open top of the main body; (c) at least one substantially horizontal shelf mounted on the inner frame; and (d) a lifting assembly operatively connected between the inner frame and the main body to selectively raise and lower the inner frame.
 11. The refrigeration unit of claim 10 wherein the lifting assembly includes a motor, and a drive mechanism actuatable by the motor and configured such that when the motor rotates in a first direction the inner frame moves upward relative to the main body, and such that when the motor rotates in an opposite second direction the inner frame moves downward relative to the main body.
 12. The refrigeration unit of claim 11 comprising a threaded rod engaged in a threaded aperture in the inner frame and connected to be rotated by the drive mechanism.
 13. The refrigeration unit of claim 12 wherein the threaded rod extends substantially vertically into the threaded aperture defined in a substantially horizontal base support member incorporated into the at least one shelf.
 14. The refrigeration unit of claim 11 comprising a plurality of pulleys and at least one cable connected to the inner frame, the outer frame, and the drive mechanism and configured to raise and lower the inner frame.
 15. The refrigeration unit of claim 14 comprising a cable drum rotatably attached to a bottom portion of the main body about a substantially vertical axis and connected to the at least one cable and connected to be rotated by the motor and the drive mechanism.
 16. The refrigeration unit of claim 15 comprising: (a) upper and lower front right, upper and lower front left, upper and lower rear right, and upper and lower rear left pulleys attached to the main body; (b) a front right cable wrapped on the drum and passing from the drum to the lower front right pulley, then up to the upper front right pulley, then down to the inner frame; (c) a front left cable wrapped on the drum and passing from the drum to the lower front left pulley, then up to the upper front left pulley, then down to the inner frame; (d) a rear right cable wrapped on the drum and passing from the drum to the lower rear right pulley, then up to the upper rear right pulley, then down to the inner frame; and (e) a rear left cable wrapped on the drum and passing from the drum to the lower rear left pulley, then up to the upper rear left pulley, then down to the inner frame.
 17. The refrigeration unit of claim 10 wherein the lifting assembly comprises a plurality of pneumatic cylinders.
 18. The refrigeration unit of claim 17 wherein the pneumatic cylinders are actuated by pressurized refrigerant fluid.
 19. The refrigeration unit of claim 10 wherein the at least one substantially horizontal shelf is laterally slidable with respect to the inner frame, and includes side panels forming a drawer.
 20. A method of providing access to an interior of a top opening storage unit, the method comprising: (a) mounting at least one substantially horizontally oriented shelf within the interior of the storage unit; and (b) operatively connecting the at least one shelf to a selectively operable lifting mechanism for vertically raising and lowering the at least one shelf relative to the unit's interior. 